Dash pot



Deb. 7, 1937. RADTKE 2,191,194

DASH POT Filed March 14, 1934 ram) adfjfe frwemor" v 5 192's Ali r z e s Patented Dec. 7, 1937 UNITED STATES MUM PATENT OFFICE DASH POT Application March 14, 1934, Serial No. 715,573

6 Claims.

This invention relates to timing or dashpot devices. It is an object of this invention to provide an improved timing or dashpot device which is relatively simple and inexpensive in construction and efficient in use.

7 The present invention contemplates a timing or dashpot device for controlling or timing the duration of the operation of rotating or other movable parts.

Another object of the invention is to provide a timing device or dashpot that is especially adapted for use in conjunction with coin controlled apparatuses for timing the operation of rotating parts such, for example, as revolvable discs, or the like.

Another object of the invention is to construct the timing device or dashpot so that the air intake thereinto may be regulated and the return or timing stroke of the piston correspondingly governed.

A further object of the invention is to construct the timing or dashpot device so that the piston therein may be kept in good and efficient working order.

Other objects will appear hereinafter.

The invention consists in the novel combination and arrangement of parts to be hereinafter described and claimed.

The invention will be best understood by reference to the accompanying drawing, showing the preferred form of construction, and in which:

Fig. 1 is a perspective view illustrating the preferred form of the present invention associated with an amusement game apparatus;

Fig. 2 is a longitudinal sectional view of a preferred form of the new timing device;

Fig. 3 is a transverse sectional view of the same on line 3-3 in Fig. 2;

Fig. 4 is a sectional detail View on line 4-4 in Fig. 3; and

Fig. 5 is a sectional view of a modified form of the new timing device.

For the purpose of illustrating the invention and its uses the same is shown in the drawing as associated with an amusement game apparatus, generally indicated at I0, this apparatus forming the subject matter of Patent No. 2,000,778 granted to John F. Meyer, May 7, 1935 on a Game apparatus, and being of the type which embodies a cabinet II within which is arranged a rotatable member in the form of a spinning disc I2 operated by suitable coin controlled mechanism associated with the coin slide I3. However, it is to be understood that the invention is not limited to the type of device with which it is shown associated but may be used in conjunction with a wide variety of devices wherever it is desired to time the duration of movement of a rotatable member, such as a spinning disc, drum, or the like.

A preferred form of the new dashpot is generally indicated at I4 and comprises a pump body or cylinder I5 in which is slidably arranged a piston I! having a flexible and expansible ring portion 36. The piston is attached to a piston rod or operating member I8. The piston-operating member I8 is slidably projected through a slot I9 formed in one end wall 20 of the cylinder; the outer end portion 2| of the piston rod or piston-operating member I8 having a lateral extension or pin 22 projecting therefrom and the inner end portion of the operating member I8 having the piston I? attached thereto.

It will be observed in Figs. 1 and 2 that the piston rod I8 is an elongated fiat strip of oblong cross-section (Fig. 3), and as seen in Fig. 2 has its innermost extremity upset to form a lateral extension 50 which rests against the inner bottom surface of the piston I l and is secured to the latter by means such as the screw 5i extended through the center portion of the piston head and threaded into the lateral bracket extension 50. It should also be observed that the elongated opening I9 in the cylinder end wall 20 is disposed eccentrically thereof and of the center line of the cylinder and the piston I! to provide a simplified construction and one which will reduce some of the effect of sidewise or lateral or torsional play on the piston rod and transform such play into rotational movement of the piston. Torsional or twisting forces exerted upon the piston rod when it is concentrically mounted, obviously tend to produce the turning of the rod about the center line through the piston, whereas lateral displacements or forces on the concentric piston rod do not tend to produce any rotational effect in the piston. However, in the case of the eccentric piston rod there is a tendency on the part of both lateral and torsional forces applied thereto to swing the same about a radius whose center is the center of the piston and whose distance is the distance between such center and the main horizontal part of the rod.

By making the piston rod I8 fiat, a considerable economy is effected in manufacturing; the ofiset or angled end 50is easily punched and tapped; the pin 22 is simply and firmly attached thereto, (more difficult with the round style of rod) as are other instrumentalities such as the spring 39.

The eccentric connection of the rod I8 has a number of advantages, among others the fact that it can be disposed very close to the mounting surface and either in or close to the plane of the operating mechanism such as 3839, etc. In this connection, the mounting bosses T are arranged in the especial manner shown, with screw holes opening into a plane tangent to that side of the cylinder nearest the eccentric rod 48. Thus the dashpot may be mounted closer to or in the plane of movement of operating members attached thereto.

Formed in one integral end wall 25 of the cylinder body I is an air inlet passage or vent 26 which opens at its inner end into the cylinder l5 at one side of the piston I1 and which opens at its outer end to the atmosphere, as at 21. Formed in this passage 26 between its ends is a valve seat 23 and arranged in the passage 26 is an adjustable air valve having a head 29 that is adapted for engagement with the seat 23. The head 29 of the air valve has a threaded shank of stem 30 which is adjustably mounted in a corresponding threaded opening 3! that is formed in a boss 24 provided on the end wall 25 of the cylinder body i5. Extending through the Wall of the cylinder [5 from the atmosphere to the interior of the cylinder, at one side of the piston I1, is a vent passage 32.

Formed on theinner side of one of the end walls of the cylinder 15, namely the end wall 20, toward which the piston moves in its timing stroke, is a substantially frusto-conical and annular formation 33 which functions as a piston expanding member, in a manner to be described presently.

As the flexible portion 36 of the piston l1 completes its timing stroke toward the wall 20 of the cylinder 15 it engages and seats upon the substantially frusto-conical formation 33 which thereby functions to spread or expand the flexible portion 36 of the piston I? radially outwardly into the annular groove 3 that is formed between the piston expanding ring 33 and the wall of the cylinder 55 (Fig. 2). And in this connection it will be noted, (Fig. 4) that at its axially outer end 4i the annular groove 34 is somewhat larger in diameter than is'the inside diameter of the cylinder I5 throughout the main extent thereof so that the expansible piston ring portion 36 is expanded radially outwardly against the inside wall of the cylinder l5 as it is forced onto the piston expander 33 at the end of the' movement of the piston in one direction in the cylinder. This spreading or expanding operation, taking place at every opera tion of the piston, keeps the flexible ring portion 35 thereof in a flexible live condition and provents the same from becoming stiif, so that the flexible wiping ring portion 36 of the piston frictionally wipes against the inner wall of the cylinder I5 at all times and forms an effective air seal therewith. In this manner the piston I1 is kept efficient and in good working order and retains its ability to form an effective air seal with the inner wall of the cylinder 55 when in use. In this manner, the piston I1 is prevented from slipping in the cylinder l5, thereby overcoming a serious objection to all prior art timing devices of the pump type.

The new dashpot or timing device is, as has been stated, shown as associated with a coin controlled mechanism, generally indicated at 48, for operating a spinning disc I 2 or other analogous movable member, and to this end the coin slide l3 carries a vertical pin 35 which engages a pivotal member 31 when a coin of proper denomination is inserted into the coin aperture of the coin slide l3 and dotted line position (clockwise) Fig. 1.

the latter is pushed inwardly to make its operative stroke. This movement of the coin slide [3 with its pin 35 in engagement with the pivotal member 37 actuates other members included with the operating mechanism G8 until finally a pivotal arm or lever 38, which is included as a part of the operating mechanism 38, is moved from full to During this movement the free end of the pivotal operating member 3% is disposed in engagement with the pin '22 and thereby pushes the piston operating member i8 inwardly (right to left, Fig. 2, and conversely, Fig. 1) against the action of yieldable means in the form of a coil spring 39 which has one end attached to the outer end of the piston-operating member l8 and which has its other end suitably anchored or fixed in the cabinet H, as at 40 (Fig. 1).

When the piston I1 reaches the inner end of its stroke and is ready to commence its return stroke the coin slide i3 is likewise ready to start back on its return stroke (to the left, Fig. 1) and the tensioned spring 39 thereupon slowly pulls the piston I? and its operating member !8 (to the left, Fig. 1, to the right, Fig. 2), thus forcing air ahead of the piston I? out of the cylinder 15 through the vent 32 until the flexible ring portion 35 of the piston ll finally engages the frustoconical formation 33 and rides up onto the latter into the annular groove 36, thereby spreading the flexible portion 36 of the piston H in the manner hereinbefore described.

This return or timing stroke of the piston IT (to the right, Fig. 2, to the left, Fig. 1) takes place slowly under the action of the tensioned spring 39 due to the fact that there is a relative vacuum formed in the area of the cylinder I5- behind the piston l I and the resistance offered by the air under atmospheric pressure in the area of the cylinder l5 in front of the piston I! so that the return of the piston rod or operating member i8 and associated parts, including the member 38, which control the spinning of the disc I2, or other movable apparatus controlled by the timing device, is thus timed.

The relative speed of the timing or return stroke of the piston ll and its operating member l3, and the member 38, and the time required therefor, may be regulated byradjusting the air valve 29-30' so as to vary the air intake into, and relative vacuum formed in, the area of the cylinder l5 behind the piston I! on its return stroke, that is, between the piston i! and the air valve 23293Ei; it being understood that the more the valve 2936 is opened the greater is the air intake and the less is the relative vacuum behind the piston on its return stroke and consequently the less will be the difference between the air pressures onopposite sides of the piston on its return or timing stroke and consequently the faster will be the return or timing stroke of the piston and the shorter the time required therefor and the shorter the duration of the operation of the disc E2 or other apparatus controlled by the tim- While in the illustrative form of the invention, shown in Figs. 1 to 4 inclusive, the frusto-conical piston expanding and spreading formation 33 is shown as located at one end of the cylinder l5 and the flexible flange portion 36 of the piston I1 is shown correspondingly positioned to engage and seat upon the piston spreader 33, in Fig. 5 I show a modified form of the new timing or dashpot device in which this relative arrangement of the piston spreader and the flexible flange of ring of the piston is reversed.

Thus the modified form of the invention, re-

" "versing the pistons, as shown in Fig. 5, and generally indicated at 4|, is substantially the same in construction and operation as the illustrative form M of the invention, shown in Figs. 1 to 4 inclusive, except that in the modification the piston rod is concentric and the piston expander 42 is formed upon the opposite end wall of the cylinder and the annular groove 44 and the flexible flange portion 43 of the piston adapted tobe received therein are correspondingly positioned. In this form of the invention the piston expander formation 42 is formed on the integral end wall 45 of the cylinder, in which wall is also arranged the air valve 46 that is identical to the air valve 232930.

However, it will be observed that the removable end wall 54 is provided with a depressed and elongated neck 56 having a reduced or conically diminishing longitudinal channel 58 communicating from the interior side of the head and the interior of the cylinder to the extremity of 'the head, and through which the piston rod 60, which in this instance may be circular in section, extends for connection with a controlled device. Adequate support is provided by the peculiarly formed neck and head structure so as to prevent undue sidewise play of the piston rod 60 relative to its piston to which it is centrally attached as at 52.

As seen in Figs. 4 and 5, the cylinder head or end wall 20 or 54 is adapted to fit flush against the end of the cylinders l4 and 4| and tobe attached to the same by means of screws 61 threaded into bosses 66 formed integrally on the cylinder casing. These bosses 66 do not appear in Fig. 5 but are disposed identically as in the case of the embodiment of Figs. 2 to 4.

Additionally, it may be noted in Figs. 1 and 2 that laterally extending mounting bosses Ill, drilled to receive mounting screws II, are extended laterally or radially outwardly of the outer cylinder wall intermediate the axial ends thereof, and have their bottommost surfaces 10' disposed substantially on a level with the outer periphery of the cylinder wall so that the cylinder may be placed upon a flat surface with the lower surfaces 13 of the bosses l closely overlying the flat surface and the mounting screws H passed into and through said surface to mount the dashpot.

In this manner, the compressing stroke is reversed, the return spring being arranged to urge rod 60 inwardly, instead of pulling outwardly as in the arrangement of Fig. 1.

Added support results from the enlarged sleeve area in close contact with the rod 60 (Fig. it being apparent that the more extensive the sleeve area in which the rod moves, the less play there will be. The conical portion 58 serves to avoid binding when the rod moves into and out of the sleeve, and moreover, serves as a grease pocket. It is of further importance to observe that the outwardly extended neck structure 55 additionally functions to prevent lateral play of the rod when the piston is withdrawn to the opposite end of cylinder 4| to that in which it is shown in Fig. 5.

While I have illustrated and described the preferred form of construction for carrying my in vention into effect, this is capable of variation and modification, without departing from the spirit of the invention. I, therefore, do not wish to be limited to the precise details of construction set forth, but desire to avail myself of such variations and modifications as come within the scope of the appended claims.

Having thus described my invention, what I claim as new and desire to protect by Letters Patent is:

1. A dashpot comprising a cylinder having an integrally formed and a removable axial end wall, valve means on said integral wall, said cylinder having an air vent intermediate said valve means and said removable end wall, a piston reciprocable in said cylinder and drive means for said piston including an elongated flat piston rod extended through said removable end wall into said cylinder eccentrically with respect to the latter and having its inner end portion upturned to form a laterally extending arm, and means attaching said arm to a substantially central part of said piston.

2. A dashpot including a cylinder having a pair of axial end walls, one of the same being removable and having an opening disposed olfcenter relative to the axis of the cylinder, an air intake positoned at one end of said cylinder and an air ventadjacent the opposite end of the same, a piston reciprocable within said cylinder, and a piston rod in the form of an elongated flat member extended through said off-center opening in said end wall and having its extremity within said cylinder upturned and secured to a substantially central point on said piston.

3. A dashpot comprising an elongated cylinder having an integral end wall and a removable end wall, adjustable intake means on said integral wall, a piston rod opening formed off-center relative to the cylinder axis in said removable wall, a piston disposed within said cylinder, and piston rod means in the form of an elongated member extended through said off-center opening and having an inner end portion extended laterally toward the center of said piston and said cylinder and attached to a substantially central point on said piston.

4. A dashpot including a cylinder having axial end walls, air intake means on one of said end walls, an air vent disposed near the opposite end of said cylinder, one of said end walls having an off-center piston rod opening, a piston reciprocable within said cylinder and a piston rod in the form of an elongated member extended through said off-center opening into the cylinder and having its inner end portion directed toward the long axis of said cylinder and secured to said piston at the center thereof.

5. A dashpot comprising a cylinder having a removable end wall with an eccentric elongated opening therein, a piston in said cylinder and a flat piston rod passing through said eccentric opening in the removable end wall and having an offset end portion attached to said piston, said cylinder having mounting lugs with engaging surfaces disposed on opposite sides of said cylinder and in a plane substantially parallel to the plane of said piston rod.

6. A dashpot including a cylinder having a substantially tubular outer wall and opposite end walls, valve means on the cylinder, a piston in said cylinder, a substantially flat piston rod having a laterally offset end portion attached to the center of said piston and extended through offcenter one of said end walls, said cylinder also having a pair of mountinglugs disposed on opposite outer sides thereof and each having an engaging opening lying in a common plane substantially tangent to a side of said cylinder and substantially parallel with the plane of said flat piston rod.

BRUNO RADTKE. 

